Seat adjuster



Dec. 6, 1960 c. H. scHAMEL ETAL 2,963,075

SEAT ADJUSTER Filed Sept. 9. 1954 N :im im 4 Sheets-Sheet 1 AT QRNEYDec. 6, 1960 c. H. scHAMEL ETAL 2,963,075

SEAT ADJUSTER Filed Sept. 9. 1954 4 SheetsSheet 2 INVENTORS awa/.5I fenif ATTOR EY Dac. 6, 1960k c. H. scHAMEL ETAL .2,963,075

SEAT ADJ USTER Filed Sept. 9. 1954 4 Sheets-Sheet 5 im 'fh- J [iINVENTORS AT ORNEY Dec. 6, 1960 c. H. scHAMEL ETAL 2,963,075 SEATADJUSTER l Filed Sept. 9, 1954 4 Sheets-Sheet 4 ATT RNEY United StatesPatent@ l sEAr-ADJUsrER Clydey H; Schamel,4 Royal-1` Qakj, and Gland` S.Semar,

Birmingham, Mich., assigner-.sto General Motors Cornoratic., Detroit.Mich-Ia corporation Qt Delaware.

FiledSept. 9, 1954,` Ser. No. 455,017 ltllaims. (Cl, 15S-e114),

This invention relates to adjustableV seats and more particularly topower means for f ore-and-arft adjustment of a vehicle seat;

InA order to facilitate the fore-andaft movement of a vehiclelseat, itis desirable to employremotely controlled power means for shifting theseat between its fore-andaft positions. This permits the driver-, evenwhile operating the vehicle, to controlv the position of the seat' at aproper and comfortable distance from the vehicle controls, such as thebrake andY accelerator pedals and steering wheel. Although there havebeen power operated seat adjusters devised for this purpose, they havebeen subject to numerous objec-tionsand? are generally very complicated.This results in a power seat adjuster'which is not pratical from acommerci-al standpoint since it is too expensive and unreliable to be`generally accepted by the public.

It is proposed to provide aY simple power operated seat adjuster thatwill be economical to manufacture. regulator is a self-containedassembly including a mounting frame or bracket which will permit theregula-tor to be installed on a vehicle as a factory-'installedaccessory or to be sold as an accessory Yfor installation on fullyassembled cars. The power means and actuating linkage for the regulatorsare constructed so as to be very reliable in operation and require theminimum amount of controls and related equipment.

When an electr-ic motor is employed for drivingl a seat adjustingmechanism, it is necessary to employ a speed reducing gear train. In thepastit has been the practice to place these speed reducing mechanisms inseparate housings which may be Vsecured either to the motor housing, thevehicle frame, or the seat frame., It is now proposed to employ a singlehousing having a speedreducing gear portion and a motor portion formedtherein which may be integrated into a self-contained seat adjustingmechanism which is economical to manufacture and contains the speedreduction mechanism, the motor, and the motion-translating mechanism.

It is also contemplated that the integral motor and speed-reducingmechanism employed maybe interchangeable with similar units utilizedA inpower operated-windows and convertible top adjusting mechanismsincorporated in the same vehicle. Due to torque characteristics and thesimplicity of control, a series electric motor is a highly desirablepower source for such adjusting mechanisms. However, as there will belarge variations in the amount .of loading present ,in the variousmechanisms t'o be adjusted, and particularly seats which may be shiftedwith or without passenger load., it is desirahleto employ a The y2,963,075 Patented Dec. e, 1960 ICC motor which has a` substantiallyconstantspeed regardless of load in such adjustingA mechanisms.Accordingly, it is proposedu to employ a seat adjusting power actuatingmechanism having-aseries motor in which the motor may beprovided withmeans that will produce a more constant speed'` regulation. with-'aresultant uniform speed or adju'stmentl It is also proposed to employa seatadjuster power mechanism hai-vingfrictionF means disposedtoprovide a frictional drag-on the armature of the motor so that when itis desired te stop the seat in a certain position, the momentum of thehigh-speed electric motor willbedissipated as soon as the motor is shutoli?. Therefore,tlie tendencyfor the seat to overrunY its position willbe greatly' reduced;

' Itis further proposed te employ a seat adjusting mechanism providedwith a speed-reducing mechanisrri'which is self-locking when the 'powersupplied is disconnected from the motor.v Thus, when the seat h as beenproperly adjusted, the momentum df the passengers sitting' on theadjusted seatduring perigds of rapidvehicle acceleration anddeceleration will not cause `foreandaift shifting ofjt-he seat. A VFromthe foregoing it will be seen that one of the primar-y objects of thisinvention isithe provision offa pQWerbperated seat adjusting mechanism"which is both compact-inV construction and inexpensive' to manufactureand which can be easily adapt'edfto` and mounted in a motor carwithoutrelatedV auxiliary devices and special operations or changes in the carstructure. A

Another object of this invention is the provision of a motiontransmitting mechanism in a seat adjusting mechanism which is adapted`especially for operation by a high-speed electric motor and which isboth simple in design as well as eiiicient and reliable in operation.

A further object of this invention is theprovision of means forvtranslating high-speed rotary motion supplied by an electric motorintorelatively low-speed translatory motion for operating a seatadjusting mechanism or the like.

These and other objects of this invention are attained by providing aseat adjustably mounted on a support for fore-and-aft movement andhaving motion equalizing means co-operating with the seat and itssupport forguiding the seat in such adjusting movement, with a poweractuating mechanism reacting between the equalizing means or the seatand the support to adjustably and se: lectively move the seat as guidedby the equalizing means. The equalizing means includes an equalizingVshaft or rod having a crank arm adjacent each end thereof which isjournaled or otherwise pivotally connected at one 4end thereof to eitherthe seat member or its support member. The opposite end of each crankarm is provided with a pivotal pin-and-slot connection with the other ofsaid members. The power actuating mechanism is a self-,coutained unitmounted on the support and including a highspeed series electric motor;a speed reducing mechanism comprising a worm gear, a worm wheel, aspring plate braking rotation thereof when the motor is deenergized, anda pinion gear driven by the worm Wheel; and a motion translatingmechanism including a sector gear driven by the piniongear and aconnecting rod for universally interconnecting the equalizing shaft orthe scatto a, point adjacent the periphery of the sector gear.V

The objects of the invention will be more clearly understood from thefollowing description of a preferred embodiment thereof in whichreference is made to the attached drawings, in which:

Figure 1 is a view in side elevation with parts broken away to show apower operable adjustable seat made in accordance with our inventiontaken substantially on the line 1-1 of Figure 2; and Figure la is anenlarged fragmentary view of a portion of Figure 1 with parts brokenaway and in section to show the speed-reducing mechanism in greaterdetail.

Figure 2 is a plan view of the seat adjuster taken on the line 2-2 ofFigure l on a reduced scale.

Figure 3 is an enlarged sectional view with certain portions broken awaytaken substantially on the line 3-3 of Figure 2.

Figure 4 is an enlarged view of the power operating mechanism similar tothe showing in Figure 2 with certain parts broken away, and

Figure 5 is a sectional view taken substantially on the line 5-5 ofFigure 4 while Figure 5a shows an alternative form of construction.

The same reference numerals are applied to corresponding partsthroughout the views.

The seat may be mounted on any conventional seatslide structure, but inthe instant embodiment, as best shown by Figures l to 3, each side ofthe seat underframe is provided with a downwardly facing channel-shapedtrack or rail member 12 riding on an upwardly facing channel-shaped railor track member 14. The lower track members 14 are in turn supportedabove the floor panel 16 of the vehicle by a plurality of supportbrackets as indicated at 18 and 20. The ange portions of thechannel-shaped upper and lower racks terminate in arcuately formed lipportions to form ball-bearing races for ball bearings interposedtherebetween as indicated at 22 and 23. The webs of the twochannel-shaped track members constitute races for a number ofanti-friction type roller bearings 24 interposed therebetween.

The motion equalizing mechanism provided to assure straight-linemovement of the seat during its back-andforth adjustment includes tworeaction levers 26, each of which is pivo-tally connected by a pin 28 toa bracket 30 secured to the upper track member 12 of the underframe ofthe seat. The two levers 26 are interconnected by a motion equalizingtorque rod or shaft 32 secured thereto adjacent their pivotalconnections with the seat underframe. The opposite ends of the levers 26are each provided with a pin 34 which engages a reaction slot 36 formedin the adjacent forward lower track supporting bracket 18 to form aslidable pivotal connection between the lever and the seat supportingmembers.

The power actuating mechanism for the adjustable seat includes amounting frame or bracket formed of the crossed members 46 and 48. Anintegral motor and speed-reduction gear unit 38 is mounted on one arm ofthe bracket member 46 which is in turn supported above the vehicle oorpanel or frame 16 by the bracket member 48. The integral motor andreduction gear unit 38 comprises a casing formed of housing members 38a,38b, and 38C; a high speed reversible series motor 39, a motor drivenworm 40a, a worm wheel 40h driven thereby, a spring plate 40a` engagingthe worm wheel and braking rotation thereof when the motor isdeenergized, and a pinion gear 40d driven by the worm wheel. A sectorgear 42 is pivotally mounted at 44 on the other arm of the bracketmember 46 to engage the pinion 40d and is reversibly driven thereby. Atubular connecting rod or pitman 50 is universally connected to thesector gear 42 by a pin 52, as best shown in Figures 4 and 5. The lowerend of the pin 52 has a head portion 54, a bulbous or spherical shankportion 56 spaced therefrom, and three stepped cylindrical portions 58,60, and 62. The bulbous portion 56 of the pin 52 is embraced by a hole64 formed 1n the arm of the sector gear adjacent the periphery thereof.A washer 66 embraces the largest diameter cylindrical portion 58 of thepin 52 and two annular O-rings 68 and 70 are interposed between the head54 and the lower face of the sector gear 42 and between the washer 66and the upper face of the gear 42. The connecting rod is formed withaligned holes of different diameters which embrace the stepped portions60 and 62 of the pin 52. The shoulders formed by these stepped portionsare drawn into abutting relation with the sides of the holes in theconnecting rod by a threadless sheet metal nut 72. It will readily beseen that this structure constitutes a universal joint comprising aball-and-socket type connection between the sector gear and theconnecting rod and the pivotal pin connection.

As shown in Figures 1, 2, 4 and 5, the opposite end of the connectingrod 50 is also universally connected to the equalizer rod 32. Theconnecting rod is provided with two holes of different diameter having apin 74 extending therethrough in parallel relation to the pin 52. Thepin 74 is retained in place axially by a nut 76 similar to 72 whichdraws a shoulder formed on the pin by a reduced diameter portion intoabutting relation with the sides of the smaller diameter hole. A shortlink member 78 is pivoted on the opposite end of the pin 74 and about apivot pin 80 carried by a yoke-shaped bracket 82 secured to theequalizing shaft 32. The pivotal connections of the link 78 about thehorizontal axis of the pivot pin 80 and the axis of the pin 74 which isnormal thereto provides a universal connection between the connectingrod 50 and the equalizing shaft 32. As shown in Figure 5a the seatactuating power means may alternatively be universally connected to theseat underframe. In this modified form a bracket 182 is secured to theseat underframe 110. An elongated connecting rod similar to theconnecting rod 50 is universally connected to the bracket 182 by a shortlink member 178 pivotally connected to the bracket 182 by a horizontallydisposed pin 180 therein and to the connecting rod about a vertical axisby a pin 174.

The reversible electric motor 39 is connected to the vehicle powersupply, not shown, through a three-way switch, also not shown, which isoperable to selectively energize the motor to shift the sector gear 42in either a clockwise direction for shifting the seat forward or in acounterclockwise direction for shifting the seat rearwardly of thevehicle. The movement of the sector gear in the fore-and-aft directionis transmitted through the connecting rod to the equalizing shaft or rodto the upper track members secured to the seat underframe in the form ofFigure l or directly to the seat underframe in the form shown in Figure5a. In either form when the equalizing rod is shifted back and forth,the two crank arm levers 26 on the equalizing shaft are caused to rotateequally about their slidable pivotal connections with the seatsupporting member and about their respective pivotal connections 28 and34 with the upper track members. This insures the well-guided equalmovement of both sides of the seat during the adjusting movement.

In addition to the inherent limiting action of the slots 36 upon thefore-and-aft seat adjustment, the track members are provided withsuitable stops, not shown, and the motor circuits, also not shown, maybe provided with suitable movement-responsive switches orcurrent-responsive relays to preventl motor overtravel or overloading,respectively. The spring plate 40e through its engagement with the wormwheel 40d provides a frictional drag on the armature of the motor sothat when it is desired to stop the seat in a certain position, themomentum of the high-speed electric motor will be dissipated as soon asthe motor is shut off. By this means the tendency of the seat to overrunits selected position will be greatly reduced. The pitch of the motordriven worm 40a is such that the worm is non-rotatable when the power isdisconnected from the motor. This renders the seat adjusting powermechanism self-locking to prevent fore-and-aft masacre E `shifting ofthe adjusted seat as a result of pushing or'pul-ling of the seat oras aresult of inertia effects during periods of rapid vehicle accelerationor deceleration.

From the foregoing description and the accompanying drawings, it will beobserved `that .the adjustment of. the seat forwardly and rearwardly maybe1 aiected with little eiort and. that the arrangement is .practicaland` efficient. While the foregoing description has been given in`detail for clarity and ease of the understanding, it is not theintention thereby to restrict the invention since the inventiveprinciples herein involved are capable of assuming other physicalembodiments' withoutdeparting from the spirit of the invention or thescope defined in the appended claims.

We claim:

1. In a motor vehicle having a support element, a seat element mountedthereon for fore-and-aft movement, and motion equalizing meanscooperating with the seat and its support for guiding the seat in suchmovement; power means connected to said equalizing means to selectivelyeffect fore-and-aft movement of said seat with respect to said support,said power means including an electric motor, reduction gearingincluding a sector gear driven by said motor, a connecting roduniversally connecting said equalizing means and said sector gear, andmeans associated with said reduction gearing for locking said lgearingand said motor when said motor is deenergized.

2. In a motor vehicle having a support element and a seat elementmounted thereon for back-and-forth movement, motion equalizing meanscooperating with the seat and its support for guiding the seat in suchmovement and including a shaft journaled on one of the first twoelements, said shaft having crank arms on its opposite ends pivotallyconnected to the other element, and power means connected to saidequalizing shaft to selectively rock the same about its pivotalconnections with said seat and said support to adjustably move the seat,said power means including an electric motor, reduction gearingincluding a sector gear and driven by said motor, and a connecting roduniversally connecting said equalizing shaft and said sector gear.

3. In a motor vehicle having a support and a seat mounted thereon forback-and-forth movement; motion equalizing means co-operating with theseat and its support at opposite sides of the seat for guiding the seatin such movement and including a shafft journaled on the seat and havingcrank arms at its ends having a pinandslot pivotal connection with saidsupport, and power means reacting lbetween said seat and said support toadjustably move the seat as guided by said equalizing means, said powermeans including a secondary support member, a rotary motor, a sectorgear mounted on said secondary support member, a speed-reducing gearmeans drivingly interconnecting said motor and said sector gear, and aconnecting rod universally interconnecting said seat equalizing shaftand said sector gear.

4. In a motor vehicle having a support, a scat mounted thereon forback-and-forth movement, and motion equalizing means co-operating withthe seat for guiding the seat in such movement, power means reactingbetween said seat and said support to adjustably move the seat as guidedby said equalizing means, said power means including a secondary supportmember, a motor and a sector gear mounted on said secondary supportmember, speed reducing gear means drivingly interconnecting said motorto said sector gear, and means operatively interconnecting said seat andsaid sector gear.

5. In an adjustable seat having a support element and a seat elementmounted thereon for back-and-forth movement, motion equalizing meansco-operating with the seat and its support at opposite sides of the seatfor guiding the seat in such movement, and power means universallyreacting between said seat and said support to ad justably move the seatas guided by said equalizing means, said power means-` including anelectric motor, a sector gear, reduction gearing drivingly'interconnecting: said motor and said sector gear, and al connecting roduniversally connecting said equalizing means and said sector gear.

6. In an adjustable seat' having a support', a seat, and seatcarryingrmeans for mounting said seat on said support for equalizedback-and-forth movement, power meansuniversall'y connected' to said seatcarrying means to -adjustably move the seat, said power means includinga rotary motor, a sector gear, reduction gearing driving- 1y interposedbetween said motor and said sector gear, said reduction gearingincluding friction means for locking said sector gear in its adjustedposition when said motor is deenergized, and a connecting roduniversally interconnecting said seat carrying means and said sectorgear.

7. In an adjustable seat having a support, a plurality of rail membersmounted on said support, a seat, and a second plurality of rail membersattached to said seat and adjustably mounting said seat on said firstplurality of rails for fore-and-aft movement, the combination comprisingan equalizer rod journaled in one or more of said second rail memberslocated on opposite sides of said seat, and power means universallyinterposed between said seat and said support to adjustably move theseat fore and aft, said power means including an integral high speedrotary motor and reduction gearing, said reduction gearing beingself-locking and having power absorption means associated therewith fordissipating the momentum of the rotary motor when the motor isdeenergized, and reaction means co-operating with said equalizer rod forguiding the seat in such fore-and-aft movement, said reaction meansincluding a plurality of spaced crank arms secured to said equalizerrod, each of said crank arms having a pin-and-slot pivotal connectionvwith said support at the end thereof.

8. In an adjustable seat having a support, a plurality of rail membersmounted on said support, a seat, a second plurality of rail membersattached to said seat and adjustably mounting said seat on said rstplurality of rails for fore-and-aft movement, the combination comprisingan equalizer rod journaled in one or more of said second rail memberslocated on opposite sides of said seat, power means interposed Ibetweensaid equalizer rod and said support to adjustably move the seat fore andaft, said power means including a high speed rotary motor, self-lockingreduction gearing integral with said motor, and said reduction gearingincluding an output gear adapted to be oscillated through a limitedradial sector -by the operation of said motor and gearing, a connectingrod universally connected at one end to said equalizing rod and at itsopposite end to said output gear and adapted to translate theoscillation of said output gear into fore-and-aft movement of saidequalizing rod, and reaction means co-operating with the journaled endsof said equalizer rod for guiding the seat in such fore-andaft movement.

9. In an adjustable motor vehicle seat having a sup port element and aseat element mounted thereon for adjustable movement, the combination,comprising motion equalizing means co-operating with the seat and itssupport for guiding the seat in such movement, said equalizing meansincluding a shaft journaled at its opposite ends on one of the first twoelements and a crank arm secured to Said shaft and pivotally connectedto said other element at its end, and rotary power means reactingbetween said equalizing shaft and said support to adjustably move theseat as guided by said equalizing means, said power means including arotary motor, a self-locking and self-braking speed-reduction gear meansdriven thereby, a sector gear driven by said gear means, and aconnecting rod universally connecting said equalizing shaft and saidsector gear.

'7 10. The invention as recited in claim 7, said power means including asector gear driven by said reduction gearing .and atconnecting roduniversally connecting said equalizing shaft and said sector gear.

References Cited in the le of this patent UNITED STATES PATENTS1,487,660 Kingston et a1 Mar. 18, 1924 2,256,818 Sperry Sept. 23, 1941lo 2,274,448. Hoover Feb. 24, 1942 2,286,108 Rousseau et al. June 9,1942 2,308,212 vScott-Iversen et al. Jan. 12, 1943 8 Baker June 6, 1944Kruzik June 26, 1951 Kaufmann May 6, 1952 Rappl Jan. 12, 1954 Barden etal. June 1, 1954 Rappl July 20, 1954 Brundage Oct. 2, 1956 Garvey et al.Oct. 15, 1957 FOREIGN PATENTS Great Britain Dec. 2, 1953 France Jan. 11,1939

